Radiation-sensitive composition, pattern-forming method and metal oxide

Abstract

Provided is a radiation-sensitive composition superior in sensitivity. A radiation-sensitive composition incudes a metal oxide having a structural unit represented by formula (1), and a solvent. In the formula (1), M represents germanium, tin or lead; R 1 represents a monovalent organic group having no greater than 30 carbon atoms which includes at least one of an electron attractive group and an unsaturated bond-containing group, and bonds to M via a carbon atom.

What is claimed is: 
     
         1 . A radiation-sensitive composition comprising:
 a metal oxide comprising a structural unit represented by formula (1); and   a solvent,   
       
         
           
           
               
               
           
         
         wherein, in the formula (1), 
         M represents germanium, tin or lead; and 
         R 1  represents a monovalent organic group having no greater than 30 carbon atoms which comprises at least one of an electron attractive group and an unsaturated bond-containing group, and bonds to M via a carbon atom. 
       
     
     
         2 . The radiation-sensitive composition according to  claim 1 , wherein
 the monovalent organic group represented by R 1  comprises the unsaturated bond-containing group, and   the unsaturated bond-containing group is at least one of an aromatic group and an ethylenic double bond-containing group.   
     
     
         3 . The radiation-sensitive composition according to  claim 1 , wherein
 the monovalent organic group represented by R 1  comprises an electron attractive group, and   the electron attractive group is at least one of a cyano group, a nitro group, a halogenated alkyl group, —COO—, and a cationic group.   
     
     
         4 . The radiation-sensitive composition according  claim 1 , wherein the structural unit is represented by formula (1-1): 
       
         
           
           
               
               
           
         
         wherein, in the formula (1-1), 
         M is as defined in the formula (1); 
         R 1A  represents: a first substituent that is a monovalent organic group having 2 to 29 carbon atoms which comprises an unsaturated bond-containing group, and bonds to the carbon atom bonding to M via one of carbon atoms constituting the unsaturated bond; a second substituent that is a monovalent organic group having 1 to 29 carbon atoms which comprises a divalent electron attractive group, and bonds to the carbon atom bonding to M via the divalent electron attractive group; or a monovalent electron attractive group; 
         R X1  represents a hydrogen atom, or an alkyl group having 1 to 5 carbon atoms; and 
         n is an integer of 1 to 3, 
         wherein
 in a case in which there exist a plurality of R 1A s, the plurality of R 1A S are identical or different, and 
 in a case in which there exist a plurality of R X1 s, the plurality of R X1 s are identical or different. 
 
       
     
     
         5 . The radiation-sensitive composition according to  claim 1 , wherein a content of the metal oxide in terms of solid content equivalent is no less than 50% by mass. 
     
     
         6 . The radiation-sensitive composition according to  claim 1 , wherein the solvent is an organic solvent. 
     
     
         7 . The radiation-sensitive composition according to  claim 6 , wherein the organic solvent comprises an alcohol solvent having 1 to 10 carbon atoms. 
     
     
         8 . A pattern-forming method comprising:
 applying the radiation-sensitive composition according to  claim 1  directly or indirectly on a substrate to provide a film;   exposing the film; and   developing the film exposed.   
     
     
         9 . The pattern-forming method according to  claim 8 , wherein a developer solution used in the developing comprises an organic solvent. 
     
     
         10 . The pattern-forming method according to  claim 8 , wherein a radioactive ray used in the exposing is an extreme ultraviolet ray or an electron beam. 
     
     
         11 . A metal oxide comprising a structural unit represented by formula (1): 
       
         
           
           
               
               
           
         
         wherein, in the formula (1), 
         M represents germanium, tin or lead; and 
         R 1  represents a monovalent organic group having no greater than 30 carbon atoms which comprises at least one of an electron attractive group and an unsaturated bond-containing group, and bonds to M via a carbon atom.